As you move from undergraduate to postgraduate study, you'll find a much stronger emphasis on self-directed learning, and an expectation that your own intellectual curiosity will drive your studies to a far greater extent. You'll need to be able to deal with a greater level of abstraction and theoretical complexity. You'll also be expected to engage with and in the most up-to-date research, and develop your own innovative ways of thinking about topics.
You'll need to develop your critical research and enquiry skills, as well as relevant technical and practical skills, and you'll become a much more autonomous learner, developing the skills of self-organisation and self-motivation. You'll also need to learn to deal with the unpredictable nature of research, and how to cope with both negative and positive results from your data and/or research. Lastly, you'll learn about appropriate professional attitudes, behaviour and values in your discipline, including learning ethical behaviours, developing academic integrity, recognising the need to reflect on methodology, and becoming part of a research community.
All of these challenges will ultimately push you forward in your area of specialism, empowering you to enhance your future opportunities.